Math - Ratios

1:2 1 apple to 2 carrots.
7:2 7 water to 2 humans.

The ratios are the relationships between two values.

Part-to-Part & Part-to-Whole

A ratio has two types of relationships:

Part-to-Part: The relationship between one part to another part.

14:10 14 blue to 10 red.
10:14 10 red to 14 blue.
Part-to-Whole: The relationship between one part and the whole, the total.

14:24 14 blue to 24 total.
10:24 10 red to 24 total.

Equivalent Ratios are ratios that have the same proportion, even if the numbers are different.

3:1 $\small(3 * 1):(1 * 1)$
6:2 $\small(3 * 2):(1 * 2)$
9:3 $\small(3 * 3):(1 * 3)$

Ratios represent a proportion that can be increased or decreased.

1:2 $\small base \div 2$
2:4 $\small base$
4:8 $\small base * 2$

4:3 $\small base \div 2$
8:6 $\small base$
12:9 $\small base * 2$